Climate Change Adaptation and Restoration of Western Trout Streams: Opportunities and Strategies

Williams, J. E., et al., 2015. Fisheries

Original research (primary data)
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Abstract

Climate change is contributing to the severity and rate of stream degradation by changing the timing of peak flows, altering flow regimes, creating more frequent and intense disturbances, and increasing stream temperatures. Herein we describe three case studies of trout stream adaptation that address existing and climate-driven causes of degradation through habitat restoration. The case studies vary in geography and complexity, but all include restoration efforts intended to address multiple causes of stream degradation and improve the resilience of these streams to floods, droughts, and wildfires. Four elements of successful climate adaptation projects emerge: (1) habitat assessments that help drive project location and design, (2) projects that directly address climate change impacts and increase habitat resilience, (3) projects that combine to achieve watershed-scale impacts, and (4) projects that include sufficient monitoring to determine their effectiveness. We describe solutions to common challenges in conducting climate change adaptation, including how to balance scientific assessments with opportunities when choosing projects, how smaller projects can be aggregated to achieve watershed-scale benefits, and how citizen science efforts can augment monitoring programs. El cambio climatico esta contribuyendo a incrementar la severidad y la tasa de degradacion de los rios a traves de la alteracion en la estacionalidad del flujo maximo, modificacion del regimen de flujos, generacion de perturbaciones mas frecuentes e intensas e incremento de la temperatura de los rios. Aqui se describen tres casos de estudio de la adaptacion de rios en donde habita la trucha, en los que se abordan las causas de la degradacion que son provocadas por el cambio climatico, mediante la restauracion del habitat. Los casos de estudio varian en cuanto a ubicacion geografica y complejidad, pero en todos se contemplan esfuerzos de restauracion enfocados a abordar multiples causas de degradacion de rios y mejoramiento de la resiliencia de estos ante inundaciones, sequias e incendios naturales. Se consideraron cuatro elementos para lograr una adaptacion exitosa al cambio climatico: 1) evaluaciones del habitat que ayuden a disenar y establecer donde llevar a cabo los proyectos; 2) proyectos que aborden directamente los impactos del cambio climatico y el incremento en la resiliencia del habitat; 3) proyectos que, al combinarse, logren resultados a nivel de cuenca hidrologica; y 4) proyectos que incluyan un monitoreo suficiente como para que se pueda determinar su efectividad. Tambien se describen soluciones a los clasicos retos que implica la adaptacion al cambio climatico, incluyendo como encontrar un balance entre evaluaciones cientificas y eleccion de proyectos, como se pueden integrar varios proyectos pequenos para conseguir beneficios a escala de cuenca y como se puede incrementar el monitoreo mediante esfuerzos ciudadanos.

Case studies

Basic information

  • Case ID: INT-107-3
  • Intervention type: Restoration
  • Intervention description:

    A variety of restoration actions were undertaken, including livestock exclusions with other long-term improvements to grazing management, channel reconstruction and reconnection of the creek to its floodplain, screening of two critical ditches, and restoration of minimum flows in the lower creek in late summer.

  • Landscape/sea scape ecosystem management: Yes
  • Climate change impacts Effect of Nbs on CCI Effect measures
    Loss of food production  Positive fish numbers
  • Approach implemented in the field: Yes
  • Specific location:

    Wasson Creek is a small second-order tributary of the Nevada Creek drainage of the Blackfoot River in Montana.

  • Country: United States of America
  • Habitat/Biome type: Streams, rivers, riparian |
  • Issue specific term: Not applicable

Evidence

  • Notes on intervention effectivness: effectiveness evaluated by comparing measure to baseline + monitoring change over time since implementation outcomes relevant for ecosystems as well because fish populations possess unique genetics and therefore needed for maintenance of genetic diversity
  • Is the assessment original?: Yes
  • Broadtype of intervention considered: Not applicable
  • Compare effectivness?: No
  • Compared to the non-NBS approach: Not applicable
  • Report greenhouse gas mitigation?: No
  • Impacts on GHG: Not applicable
  • Assess outcomes of the intervention on natural ecosystems: Yes
  • Impacts for the ecosystem: Positive
  • Ecosystem measures: fish numbers
  • Assess outcomes of the intervention on people: No
  • Impacts for people: Not reported
  • People measures:
  • Considers economic costs: No
  • Economic appraisal conducted: No
  • Economic appraisal described:
  • Economic costs of alternative considered: No
  • Compared to an alternative: Not reported

Evaluation methodology

  • Type of data: Quantitative
  • Is it experimental: No
  • Experimental evalution done: Not applicable
  • Non-experimental evalution done: Empirical case study
  • Study is systematic:

Basic information

  • Case ID: INT-107-2
  • Intervention type: Restoration
  • Intervention description:

    reconstruct the historic Crow Creek channel and restore the natural hydrologic processes that had been interrupted when the channel was straightened

  • Landscape/sea scape ecosystem management: Yes
  • Climate change impacts Effect of Nbs on CCI Effect measures
    Soil erosion  Positive no specific measure given, outcome stated by authors
    Loss of food production  Positive fish numbers
  • Approach implemented in the field: Yes
  • Specific location:

    The Salt River drainage in Wyoming and Idaho is a major tributary to the iconic South Fork of the Snake River

  • Country: United States of America
  • Habitat/Biome type: Streams, rivers, riparian |
  • Issue specific term: Not applicable

Evidence

  • Notes on intervention effectivness: effectiveness evaluated by monitoring change in measures over time (including before intervention implemented) "not only are there more fish collected in surveys (with fairly stable averages of 25 sh captured at our sites before remediation and 215 after), but there is increasing evidence of successful spawning as indicated by the numbers of young-of-year sh. Larger, migratory-sized sh are also more common. Prior to culvert replacement, nearly all sh collected were less than 100 mm total length, but after sh passage was restored, LCT in the 200–300 mm total length class were col- lected. These improvements held true even in 2012, one of the worst drought years recorded. A" fish numbers also outcome for ecosystem health because fish population are genetically distinct, implications for genetic diversity maintenance
  • Is the assessment original?: Yes
  • Broadtype of intervention considered: Not applicable
  • Compare effectivness?: No
  • Compared to the non-NBS approach: Not applicable
  • Report greenhouse gas mitigation?: No
  • Impacts on GHG: Not applicable
  • Assess outcomes of the intervention on natural ecosystems: Yes
  • Impacts for the ecosystem: Positive
  • Ecosystem measures: qualitative assessment from aerial photography of habitat improvement, important for many types of wildlife fish numbers
  • Assess outcomes of the intervention on people: No
  • Impacts for people: Not reported
  • People measures:
  • Considers economic costs: No
  • Economic appraisal conducted: No
  • Economic appraisal described:
  • Economic costs of alternative considered: No
  • Compared to an alternative: Not reported

Evaluation methodology

  • Type of data: Quantitative
  • Is it experimental: No
  • Experimental evalution done: Not applicable
  • Non-experimental evalution done: Empirical case study
  • Study is systematic:

Basic information

  • Case ID: INT-107-1
  • Intervention type: Restoration
  • Intervention description:

    Maggie Creek Watershed Restoration Project to enhance 132 km of stream, 800 ha of riparian habitat, and 16,200 ha of upland watershed in the basin. Restoration actions included the removal of existing stress- ors, in this case, livestock overgrazing; degradation of stream, riparian, and wet meadow habitats; and isolation of tributaries from the mainstem Maggie Creek. Although the project included a number of components, including riparian plantings and fencing, a conservation easement, and water developments, the most important change was application of prescriptive livestock grazing practices to limit hot season grazing. To safeguard the entire system from nonnative sh invasion, a large instream barrier was installed in 2012 below the reconnected part of the watershed near the Humboldt River.

  • Landscape/sea scape ecosystem management: Yes
  • Climate change impacts Effect of Nbs on CCI Effect measures
    Loss of food production  Positive number of fish collected in surveys numbers of young-of-year fish (indicator of spawning success) size of migratory fish
  • Approach implemented in the field: Yes
  • Specific location:

    Maggie Creek in northeastern Nevada

  • Country: United States of America
  • Habitat/Biome type: Streams, rivers, riparian |
  • Issue specific term: Not applicable

Evidence

  • Notes on intervention effectivness: effectiveness evaluated by monitoring change in measures over time (including before intervention implemented) "not only are there more fish collected in surveys (with fairly stable averages of 25 sh captured at our sites before remediation and 215 after), but there is increasing evidence of successful spawning as indicated by the numbers of young-of-year sh. Larger, migratory-sized sh are also more common. Prior to culvert replacement, nearly all sh collected were less than 100 mm total length, but after sh passage was restored, LCT in the 200–300 mm total length class were col- lected. These improvements held true even in 2012, one of the worst drought years recorded. A"
  • Is the assessment original?: Yes
  • Broadtype of intervention considered: Not applicable
  • Compare effectivness?: No
  • Compared to the non-NBS approach: Not applicable
  • Report greenhouse gas mitigation?: No
  • Impacts on GHG: Not applicable
  • Assess outcomes of the intervention on natural ecosystems: Yes
  • Impacts for the ecosystem: Positive
  • Ecosystem measures: qualitative assessment from aerial photography of habitat improvement, important for many types of wildlife
  • Assess outcomes of the intervention on people: No
  • Impacts for people: Not reported
  • People measures:
  • Considers economic costs: No
  • Economic appraisal conducted: No
  • Economic appraisal described:
  • Economic costs of alternative considered: No
  • Compared to an alternative: Not reported

Evaluation methodology

  • Type of data: Quantitative
  • Is it experimental: No
  • Experimental evalution done: Not applicable
  • Non-experimental evalution done: Empirical case study
  • Study is systematic: